I think being ambiguous on it, rather than picking it as a hill to die on as the Dems did, would have been the smartest play.
But you could well be right and I guess only time is going to tell.
I think he could have simply batted off the questioning as a lot of it was bait from people who would never vote for him anyway, as per above. Also, as you say, it's a bit foolish to choose a position that is polar different to the one you had a few years ago on this matter rather than simply keeping his own counsel about it.
But again as per above, I guess time will tell.